I am using six stereo amps with all 12 channels actively driven. Each stereo amp is run as a mono-bloc though i.e. both channels of one amp sharing the load on the right bank of tweeters and both channels of an identical amp feeding the right bank of tweeters, etc... This same system using multiple other amps is utilized all the way down through the frequency range.
This approach increases channel separation by reducing crosstalk, improves dynamic range, increases headroom, increases control over the drivers via reduced sag in the power supply, improves sound quality by allowing the amps to stay in Class A longer due to the reduction in pull from any given channel via sharing the load, increases the damping factor by increasing the impedance that the amp would see as compared to only having one channel driving all of the drivers in that bank, etc...
In the future, i may end up going to a four way system, which will require two more stereo amplifiers and a crossover change. I think that this will give me even better performance, albeit at increased cost and complexity. Like anything else, the pursuit of excellence in any given category is met with diminishing returns and increased expense.
Other than that, you are on the right path and what you want to do should work out quite well. So long as you can find a way to gain match the individual amps to each other AND gain match the "hi" & "lo" channels of each amp, you should end up with the best of both worlds i.e. mono-bloc's that are voice-matched to your listening preferences through-out the frequency range. This is exactly what i did, but with the aid of an active crossover. Sean
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